1. Field of the Invention
The present invention relates to an aluminum alloy with excellent decorativeness, which is used, for example, for slide fastener constituent members, such as the elements, stoppers, slider, and pull tab of a slide fastener, and for fastener products such as snap buttons, ordinary buttons, and various types of clasps.
2. Description of the Prior Art
The slide fastener constituent members, for example, have up to now mainly been made of copper alloys, including red brass, brass, and other such copper-zinc alloys, and nickel silver and other such copper-zinc-nickel alloys. The color of these alloys, be it copper color, gold color, or silver color, is determined by the materials used. The applications in which slide fasteners have been used in recent years have required them to have an aesthetically pleasing appearance, so there has been a need for slide fastener constituent members of various colors.
A slide fastener of various colors has been disclosed, for example, in Japanese Utility Model Registration No. 2587180, in which elements (teeth) composed of aluminum or an alloy thereof are subjected to anodizing, electroplating, electrodeposition, or another such electrochemical surface treatment.
However, when an existing aluminum alloy (such as JIS 5183) is subjected to an electrochemical surface treatment, the resulting slide fastener elements of various colors tend to have poor metallic gloss, and when the alloy composition is adjusted or when an existing aluminum alloy (such as JIS 5052, 5056, or 5154) is selected so as to emphasize metallic gloss, the mechanical properties, particularly strength, required by the application, and are compromised, so there are practical limitations to this approach.